Independently positionable and programmable key switches

ABSTRACT

An independently positionable key switch including a key base having a key cap receiving opening and at least one gripping feature operative to facilitate gripping of the key base. An actuatable key cap is arranged in the key receiving opening of the key base. The key cap is actuatable between an unactuated position and an actuated position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of pending U.S. patentapplication Ser. No. 10/246,762, to Rix et al. for “Computer InputDevice with Individually Positionable and Programmable Input Members”,filed Sep. 19, 2002, the entire contents of the disclosure of which arehereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to computer input devices. In particular,the present invention relates to improvements to the design,construction, and assembly of independently positionable andprogrammable key switches.

BACKGROUND OF THE INVENTION

Recent advances in computer input technology have provided arevolutionary new platform for tactile input mechanisms. Individuallypositionable and programmable keys can provide significant advantagesover a traditional keyboard. The user can specify the specific locationand function of each key, instead of merely adjusting to one particularlayout offered by a traditional keyboard.

SUMMARY OF THE INVENTION

An independently positionable key switch including a key base having akey cap receiving opening and at least one gripping feature operative tofacilitate gripping of the key base. An actuatable key cap is arrangedin the key receiving opening of the key base. The key cap is actuatablebetween an unactuated position and an actuated position.

A method for assembling, programming and testing a key switch. The keyswitch including a key base having a key cap receiving opening. Anactuatable key cap is arranged in the key receiving opening. The keyswitch also includes an inductive resonant circuit. The method includesplacing the key base in functional proximity to a reader, assembling thekey cap and the key base and actuating resonant circuit during theassembly step.

An independently positionable key switch including a key base. Anactuatable key cap is operatively connected to the key base. The key capis actuatable between an unactuated position and an actuated position.At least one of an identity indicator and a status indicator isassociated at least one of the key cap and the key base.

An independently positionable key switch including a key base. Anactuatable key cap is operatively connected to the key base. The key capis actuatable between an unactuated position and an actuated position. Acoil of a resonant radio frequency inductive circuit is incorporated inor on one of the key base and the key cap.

A method for switching a radio frequency inductive circuit. The methodincludes bringing the circuit into and out of resonance.

BRIEF DESCRIPTION OF THE DRAWINGS

Objects and advantages of the present invention will be more clearlyunderstood from the following specification when considered inconjunction with the accompanying drawings, in which:

FIG. 1 represents a perspective view of an embodiment of a positionablekey from the prior art.

FIG. 2 represents a perspective view of an embodiment of a positionablekey in an unpressed state.

FIG. 3 represents a perspective view of the embodiment of a positionablekey, shown in FIG. 2, in a pressed state.

FIG. 4 represents a view of grasping the key base of the embodiment of apositionable key shown in FIGS. 2 and 3.

FIG. 5 represents a view of an attempt to grasp the key cap of theembodiment of a positionable key shown in FIGS. 2-4.

FIG. 6 represents an exploded view of an embodiment of a positionablekey.

FIG. 7 represents a perspective view of the inside of the embodiment ofa key base shown in FIG. 6.

FIG. 8 represents a perspective view of the underside of the embodimentof a key cap shown in FIG. 6.

FIG. 9 represents a perspective view of the underside of the embodimentof a dome shown in FIG. 6.

FIG. 10 represents a top view of the embodiment of a printed circuitboard shown in FIG. 6.

FIG. 11 represents a perspective view of the embodiments of the key baseand printed circuit board shown in FIGS. 6, 7, and 10 in an assembledstate.

FIG. 12 represents a perspective view of the embodiments the key base,printed circuit board, and dome shown in FIGS. 6, 7, 9, and 10 in anassembled state.

FIG. 13 represents a perspective view of the embodiments of the keybase, printed circuit board, dome, and key cap shown in FIGS. 6-10 beingassembled in the proximity of a reader.

FIG. 14 represents a cross sectional view of an embodiment of apositionable key in an unpressed or unactuated state.

FIG. 15 represents a cross sectional view of the embodiment of apositionable key, shown in FIG. 14, in a pressed or actuated state.

FIG. 16 represents a perspective view of an embodiment of a positionablekey including an embodiment of a key identity label on the key base.

FIG. 17 represents a perspective view of an embodiment of a positionablekey including an embodiment of an electronically changeable displaymeans on the key cap.

FIG. 18 represents a cross sectional view of an embodiment of apositionable key including an embodiment of an embedded coil and aresonant switch with the key in a partially pressed state.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention provide a superior designfor individual key switches. The design provides advantages in thedesign, mechanical construction, and assembly of the positionable keys.

The design of preferred embodiments of the present invention caneliminate a gap or edge between a key cap and its underlying supportstructure. In a traditional keyboard, such a gap may not be a concern.Nearby keys are arranged so as to prevent the user from easily gainingpurchase under a key cap and inadvertently prying it loose. In a single,positionable key, however, a gap between the key cap and its underlyingsupport structure can cause problems. To reposition a key, it isnecessary to grasp it. Preferred embodiments of the present inventionmay provide an identifiable gripping surface and helps to prevent a userfrom inadvertently grasping the key cap. Grasping the key cap may causemechanical stress between the cap and base, or even result in theinadvertent removal of the key cap from the key base.

Additionally, preferred embodiments of the present invention may includefeatures in the key base geometry that assist in their designed use. Forexample, moving and repositioning a positionable key is best done bygrasping the key by its base. For grasping purposes, preferredembodiments of the present invention provide key base side walls thatmay be high enough to provide adequate purchase by the user. However,when using a key, it is desirable to have lower key base side walls, toprevent interference with the user's finger when pressing the key cap.It is also desirable to have the overall height of the key assemblyminimized while providing adequate key cap travel. Preferred embodimentsof the present invention address design tradeoffs between grasping andpressing positionable keys.

Preferred embodiments of the present invention include a simpleconstruction and assembly of positionable keys, which can eliminatenumerous parts and interconnect means, such as solder or electricalconnectors, that are cumbersome, time consuming, and cost money. Alongthese lines, preferred embodiments of the present invention caneliminate complicated mechanical switches, and can combine features of asingle key assembly part for multiple purposes.

Preferred embodiments of the present invention may provide amechanically stable interconnect between a key base and a key cap, whilesimultaneously optimizing the electrical characteristics of theidentification and communications electronics within the positionablekey. For positionable keys that rely on radio frequency induction forcommunication, the embedded electronic circuit typically should bedesigned for optimum magnetic flux capture within the space available.The mechanical design of a positionable switch typically should providea robust structural support while also complementing the electricalrequirements of the embedded radio frequency circuit.

Furthermore, embodiments of the present invention may includeidentification to label the identity and/or function of positionablekeys. For a traditional keyboard, the function of a key, and itscorresponding label identifying the key, are usually the same. Forexample, a key that produces the letter “Q” (its function) is typicallylabeled with the character “Q” printed on the top surface of the key cap(its label). For traditional keyboards, having identical functions andlabels does not pose a problem, because the function and positions (andtherefore, identity) of the keys are fixed. For positionable andprogrammable keys, however, it may be necessary to specify a keyidentity independently from key function. Because the location of apositionable key is not fixed, a user must be able to differentiate eachkey from any other key, and also identify its function quickly andeasily.

Embodiments of the present invention may also include means of switchinga resosnant circuit in ways that do not require mechanical contactbetween the switching means and the resonant circuit.

Preferred embodiments of the present invention provide importantimprovements to the design, construction, and/or assembly ofpositionable keys. These improvements can include an integrated designof a key cap and key base, where the key base provides a means tocapture the key cap in a manner that inhibits inadvertent grasping ofthe cap, improves the ruggedness and reliability of the key, and reducesthe mechanical stress that results from inadvertently grasping the keycap.

Additionally, preferred embodiments of the present invention can includeone or more of various gripping features. One example of a grippingfeature includes side scoops on the key base structure. The side scoopscan provide a visual indicator of the preferred location for graspingthe positionable key. The side scoops also provide a more comfortableand natural surface for grasping the positionable key. The grippingfeatures may also or alternatively include one or more surface contourand/or surface texture features.

Preferred embodiments of the present invention may also include asurface area on the key base that is large, so as to help ensure that auser gripping the key to move it will have sufficient purchase toaccomplish the move without needing to also grasp the key cap. Alongthese lines, opposing portions of the side of the key base may be tallerthan the other side portions. The large side wall portions may providean increased area for grasping, provide a location for side scoops,and/or provide more material for easier grasping, while not interferingwith the normal key operation. Furthermore, preferred embodiments of thepresent invention may also include regions of the side wall that arelower than the other portions. The lower portions can permit a key capto be operated without the key base interfering with the finger of theuser.

Embodiments of the present invention may also include a mechanical keyassembly that is easy to assemble, but difficult to disassemble duringtypical use. The disclosed design provides for a less-complicated,snap-together assembly of the major components required for thepositionable key.

Preferred embodiments of the present invention may also include a methodto assemble, test, and, if necessary, program the positionable key in asingle step. Methods according to the present invention can lowermanufacturing cost and are less complex than designs and methodsaccording to the prior art.

Embodiments of the present invention may also provide a switching meansthat includes a moldable pill actuator. The pill type actuator mayprovide a lower cost switching means than a mechanical switch component,while maintaining a switch resistance low enough to successfully operatea high-Q type inductive resonant circuit.

Preferred embodiments of the present invention also include anintegrated component that includes a single piece key dome, a mechanicalreturn, a switch actuator, and a cover to protect an underlyingintegrated circuit. The dome may be molded. This single piece dome mayprovide multiple integrated functions, improved key reliability, andlower manufacturing costs.

As described herein, embodiments of the present invention may alsoprovide a positionable key design with a central column support inconjunction with side catches that may provide superior mechanicalsupport and optimized flux capture in radio frequency inductivelycoupled systems.

Additionally, the present invention may also include a novel means ofspecifying the identity of a positionable key independently from itsfunction. Furthermore, the present invention may include a means oflabeling the function of a positionable key dynamically.

A typical prior art design of a positionable key 20 is shown in FIG. 1.In this prior art “clamshell” design, a key cap 10 is mounted on aswitching means, or switch 12 that is secured to a key base 14. Theswitch 12 provides two functions, an electrical contact to close anelectrical circuit when in a pressed state, and a spring function toprovide a mechanical restorative force to return the key cap 10 to anunpressed state. The positionable key 20 of the prior art includes a gap16 between the key cap 10 and the key base 14. The gap 16 allows the keycap to move in response to being pressed. Our testing has found that thedesign of the positionable key 20 allows for improvement. In particular,positionable keys 20 are typically intended to be grasped andrepositioned by a user. The normal action of grasping the positionablekey 20, however, often leads to inadvertently grasping the key cap 10instead of the more mechanically robust key base 14. Furthermore, thegap 16 allows a user to gain purchase underneath the key cap 10,frequently resulting in increased mechanical stress upon, or evenremoval of, the key cap 10.

An embodiment of the present invention that improves upon the prior artdesigns is shown in FIG. 2. A positionable key 30 contains a key cap 32that is captured securely by a key base 34. In this embodiment, theentire lower edge of the key cap 32 is shrouded by the key base 34,inhibiting the ability of a user, under normal use, to pry the key cap32 loose. Furthermore, as shown in FIG. 5, this shrouded design canlimit the ability to grasp the key cap 32 from the sides. When a userattempts to grasp the key cap 32 between a finger 44 and thumb 46, thegeometry of the positionable key 30 prevents a secure purchase on thekey cap 32. Grasping or pulling on the key cap 32 typically results inthe finger 44 and thumb 46 slipping from the key cap 32. The exposedportion of the key cap typically is insufficiently high to permit a userto gain enough purchase on the key cap to remove the key from a surfaceto which it is adhered. Similarly, the key base typically has a heightsufficient to permit a user to grip the key base only and remove the keyfrom a surface to which it is adhered.

Referring back to FIG. 2, a preferred means of attaching thepositionable key to a desired surface is with an adhesive 42. Inpreferred embodiments, the adhesive is a soft polyurethane compositionthat provides a non-permanent, mechanical, surface adhesion. Of course,many other attachment means may also be suitable, including, but notlimited to: magnets, suction cups, hook and loop fasteners, and otherattachment means known in the art. In preferred embodiments, theadhesive 42 is affixed with permanent glue to the bottom of the key base34. Typical properties of the adhesive 42 produce a temporary bond to asurface that is strong in tension, but weak in shear. Using a properformulation of the adhesive 42, preferred embodiments will demonstratesecure adhesion to a surface while pressing the positional key 30, yetwill yield easily with a slight rotational twist of the key base 34.

To facilitate the grasping and/or twisting motion needed to remove thepositionable key 30, the key base may include one or more grippingelements. The gripping elements are operative to facilitate gripping ofthe key. The gripping elements may include surface contours, surfacetextures and/or other features that permit the key to be gripped andremoved. The gripping elements may be located on any portion or portionsof the surface of the key base. The gripping elements may be continuousor discontinuous and may be employed alone or in combination.

The gripping elements in the embodiment shown in FIG. 2 include sidescoops 36 provided on opposite sides of the key base 34. The side scoop36 shown in FIG. 2 is matched by an identical scoop, hidden in theperspective view shown in FIG. 2, on the opposite side of the key base34. While the embodiment shown in FIG. 2 includes two side scoops, otherembodiments may include one or more than two. One side scoop could stillfacilitate the gripping and removal of a key, while more than two sidescoops could permit a user to grip the key in a variety of positions.Keys having similar or different shapes than the shape shown in FIG. 2could include side scoops or other gripping elements that are not onopposite sides of the key base. Also, as discussed above, one or moregripping elements may be included on only one side of a key. One exampleof a key having another shape could be an arrow shaped key. Such a keycould gripping element(s) on only one side or on two sides that are notexactly opposite, but at an angle to each other. In the end, one or moregripping elements alone or in combination may be utilized on any portionor portions of the surface of a key to facilitate the gripping of thekey.

A gripping element that includes a side scoop, such as side scoop 36shown in FIG. 2, may provide a gripping surface on the key base 34 to begrasped more easily. A side scoop or other gripping element(s) may alsoprovide a visual indication of one or more preferred areas to grasp.Gripping in preferred areas may assist a user in repositioning thepositionable key 30. The side scoops 36 may be textured to providebetter surface friction. The side scoops 36 may be convex or concave,and may employ other gripping features, such as ridges, ribs, bumps,and/or any other surface feature, contour, texture to facilitategripping the key base. Such ridges, ribs, bumps, and/or any othersurface feature, contour, texture could also be used alone without theside scoop(s). This means that a key base could include one or moregripping elements alone or in combination.

To facilitate gripping of the key base by a user, the height of at leastone portion of one or more of the side walls of the key base may begreater than other portions of the side walls of the key base. Inembodiments that include one or more side scoops, the side scoop(s) maynot extend all the way to the top of the key base, where a key capreceiving opening is arranged. Such an embodiment is shown in FIG. 2.The embodiment shown in FIG. 2 includes opposing extended or raisedareas 38 on the walls of the key base 34 to assist grasping. The areas38 provide additional material in the key base 34 for the fingers togain purchase.

In the embodiment shown in FIG. 2, rather than including a space orraised area 38 between the top of the side scoop and the top of the keybase, the side scoop could extend all the way to the top of the key basewhile the side of the key base shown in FIG. 2 with the side scoop wouldhave the same height. Alternatively, the side of the key base shown inFIG. 2 with the side scoop could have the same height as shown in FIG.2, but the side scoop omitted. Whether or not the side scoops areincluded, one or more other gripping elements could also be included.

FIG. 4 illustrates advantages that may be provided by the side scoops 36and the extended height areas 38. When grasping the key base 34 betweenthe finger 44 and the thumb 46, the side scoops 36 and the extendedheight areas 38 help to provide a secure location where a user cancomfortably gain purchase on the key base 34 without inadvertentlygrasping the key cap 32.

To facilitate operation of the key cap by a user, the height of at leastone portion of one or more of the side walls of the key base may belower than other portions of the side walls of the key base. The regionhaving a lower side wall height is lower in the sense that it is loweror closer to the bottom edge of the key base than other sides or sideportions of the key base. According to some embodiments, the loweredarea or areas is or are at a level that is at or slightly below thelevel of the key cap when depressed. Typically, the lowered area couldbe as low as desired but typically not so low that the bottom edge ofthe key cap is exposed or that a gap is created between the lower edgeof the key cap and the upper edge of the key base. However, in someembodiments, a gap could exist.

The embodiment of the key base shown in FIG. 2 includes a lowered wallportion, or lowered area 40 having reduced height. When the positionablekey 30 is in the pressed state, the lowered area prevents a finger fromcontacting the key base 34. As shown in FIG. 3, positionable keys aregenerally pressed from a preferred direction. The lowered area 40prevents the finger 44 from contacting the key base 34 under normal use.The lowered area 40 allows the key cap 32 to be operated through itsfull range of motion in a manner that adds comfort by eliminating or atleast minimizing contact between the key base 34 and the finger 44. Inpreferred embodiments, an identical lowered area 40 is provided on theopposite side of the key base 34. This identical lowered area (notshown) allows the positionable keys to be used comfortably from eitheropposing side.

FIG. 6 illustrates component assembly of an embodiment of a key switchaccording to the present invention. The components of the positional key30 assembly include: the key cap 32, a flexible dome, or dome 48, aprinted circuit board, or PCB 50, the key base 34, and the adhesive 42.The present invention may include elements to guide the actuation of thekey cap and to secure the key cap to the key base. The elements toaccomplish these functions may be separate or partially or entirelycombined. In the embodiment shown in FIG. 6, the primary mechanicalsupport of the positional key 30 is provided by a vertical central post,or post 52 in the center of the key base 34. The post 52, shown in FIG.7, provides a structural column to align and support the PCB 50, thedome 48, and the key cap 32. The key cap 32 slides over the post 52through a fitted collar, or collar 58, shown in FIG. 8. The mechanicalfit between the collar 58 and the post 52 constrains the key cap to moveperpendicular to the key base. Although this embodiment includes acircular post 52 and collar 58, any other suitable geometry may be used.For example, the collar could be square, triangular, or oval or have anyother shape. Alternately, the collar 58 may be located on the base 34,and the post 52 may be located on the cap 32, without altering theimportant associated functions. Also, a key switch according to thepresent invention could include more than one post and collar.

To secure the key cap and the key base together, the present inventionmay include one or more tabs on the key base and/or key cap. The tabscould be located on any portion of the key cap and/or key base,including the post or collar. Each tab may engage a tab recess and stopon the other of the key base and key cap as described below.

The embodiment shown in FIG. 8 includes a pair of opposing tabs 60 onthe key cap 32. Tabs 60 travel in a corresponding pair of tab recesses54 in the key base 34 shown in FIG. 7. A pair of opposing tab stops 56on the key base 34, shown in FIG. 7, captures the key cap 32 by blockingthe travel of the tabs 60. The combined mechanical interaction of thepost 52, the collar 58, the tabs 60, the tab recesses 54, and the tabstops 56 produces a robust and secure motion of the key cap 32 inrelation to the key base 34. As shown in the cross sectional drawings ofthe positional key 30 in FIG. 14 and FIG. 15, the post 52 and the collar58 combine to constrain the key cap 32 to move perpendicular to the keybase 34. The tabs 60 travel in the tab recesses 54, and constrain thekey cap 32 from rotating during operation. The angled design of the tabs60 allow the key cap 32 to be snapped easily into the key base 34 duringassembly. Once assembled, the tabs 60 catch on the tab stop 56,preventing the key cap 32 from being removed easily from the key base34. FIG. 8 shows just one arrangement of tabs, tab stops and tabrecesses. As noted above, the number and location of the tabs, tab stopsand tab recesses may vary so as to reliably connect the key base and keycap. This may particularly be true for keys having different shapes thanthe key shown in the figures.

In preferred embodiments of the present invention, the mechanical switch12 of the prior art may be replaced with a flexible molded dome, or keydome 48. In preferred embodiments, the dome 48 may be molded from aflexible silicone rubber composition. The key dome 48 may provide asimple structure that may perform the same spring function of themechanical switch 12. The restorative mechanical force that returns thekey cap 32 to its unpressed, unactuated state is supplied by a flexibleweb, or web 64. The web 64 is designed is to provide a desirableforce-deflection response of the key cap 32. As shown in FIG. 14 andFIG. 15, the web 64 deforms when the key cap 32 is depressed duringactuation. When the key cap 32 is released, the web 64 returns to itsuncompressed state, pushing the key cap 32 back to its unpressedlocation.

A key switch according to the present invention may also includeelectrical switching elements. According to one embodiment, theelectrical switching capability of the key dome 48 may provided by anelectrically conductive pill, or pill 66. When the positionable key 30is pressed, the pill 66 connects the interleaved fingers of a switch 70located on the PCB 50, shown in FIG. 10. For positionable keys 30 thatrely on radio frequency induction circuitry to communicate, thepreferred composition of the pill 66 includes silver nodules impregnatedin a silicone rubber. This material, referred to as a silver dust pill,is available from ITT Industries, headquartered in White Plains, N.Y.The silver matrix composition may provide optimal price and performancecharacteristics. According to their manufacturer, the silver dust pillstypically provide a contact resistance of less than 1 Ohm. Commonconductive carbonized rubber pills may also be used. However, theconductive carbonized rubber pills produce an undesirably highresistance path for high-Q inductive circuits. Alternately, a solidmetallic disk type pill may also be used. Metallic disk type pillsprovide a very low resistance contact path. However, our experience hasshown that the metallic disks are more expensive and are moremechanically abrasive to the switch 70 than silver matrix pillcomposition of preferred embodiments.

Along with the switching and mechanical spring functions describedabove, the key dome 48 may also protect an integrated circuit, or IC 68located on the PCB 50 as shown in FIGS. 6, 10, and 11. The IC 68 maytypically be an RFID integrated circuit. The IC 68 may be a bare diemounted on the PCB 50. The key dome 48, shown in FIG. 8, may include anIC well 72 that covers and protects the IC 68. The IC well 72 mayprovide a barrier that keeps out moisture and foreign particles that thepositionable key may be exposed, such as, for example, from anaccidental liquid spill. The IC well 72 may protect the IC 68 frompotential damage from these foreign materials.

The integrated structure of the key dome 48 may provide a single piececonstruction with mechanical, electrical, and protective properties. Thekey dome 48 may also provide a simplified assembly when compared to theswitch 12 of the prior art. The key dome 48 merely needs to be droppedinto position above the PCB 50 during construction of the positionablekey 30.

As in the embodiment shown in FIG. 10, the electrical design of the PCB50 may complement the mechanical structure of the positionable key 30.As is well known in the art, a resonant radio frequency inductivecircuit may be built by connecting a coil 70 to the IC 68 designed forsuch a purpose. In the embodiment shown in FIG. 10, an electricalbridge, or jumper 71 is used to connect the outside of the coil 70 tothe IC 68 without electrically shorting the coil traces. For optimumperformance, the coil inductance typically is matched to the circuitcapacitance to make the circuit resonant at a specified frequency usingthe relationship F∝1/√(LC). To optimize the circuit performance, it maybe desirable to maximize the magnetic flux capture for a given circuitinductance and capacitance. The practical effect of these relationshipsis that the diameter of the coil 76 typically should be made as large aspossible, within the mechanical constraints of the positionable key 30.Locating the post 52 at the center of the positionable key 30 inpreferred embodiments may have an advantage of using the area inside thecoil to provide a pass-through hole 74. By placing the primarymechanical structure of the key 30 at the center, the diameter of thecoil 76 may be maximized within the constraints of the overall design.

Preferred embodiments of the present invention may also provide agreatly simplified construction and assembly over the prior art.According to one embodiment, the positional key 30 may be built bystacking the appropriate components and then snapping the key cap 32into the key base 34. FIG. 11 shows a construction step according topreferred embodiments. In the step shown in FIG. 11, the PCB 50 isplaced into the key base 34 over the post 52. Next, as shown in FIG. 12,the dome 48 may be placed over the PCB 50 in the key base 34. Tocomplete the assembly, the key cap 32 may be aligned and snapped intothe key base 34, as shown in FIG. 13. This snap together assemblygreatly reduces the complexity of manufacturing the positionable key 30.

FIG. 13 also shows another advantage of preferred embodiments of thepresent invention. Along these lines, if the positionable key 30 isassembled in the proximity of a radio frequency identification reader,or reader 80 described by the prior art, the positionable key 30 may beprogrammed and tested as it is assembled. As described above, toconstruct the positionable key 30, it is necessary to snap the key cap32 into the key base 34. If the key is constructed properly, this shouldcause the pill 66 to close the switch 70. The reader 80 may scan forpressed keys in its proximity, as described in our prior patentapplication. The reader may detect the presence of a valid pressed keyand signal when a positionable key 30 is detected, for example byilluminating a signal LED 82. In one embodiment of the invention, if thereader signals that it can detect a key, then the positionable key 30 isproperly assembled and is electrically functioning. If the reader doesnot signal, then something is wrong with the positionable key 30 or oneof its components. By constructing a positionable key 30 in the vicinityof the reader 80, the electrical function of the key may be verified atthe time of manufacture. Furthermore, in preferred embodiments, the IC68 of the newly created positionable key 30 may be initialized andprogrammed by communicating with the reader 30 at this time. Informationabout the key identity and other characteristics such as key color maybe loaded into the IC 68 at the time of manufacture and testing. Theability to construct, test, and/or program the positionable key 30 in asingle step provides a dramatic improvement to manufacturing efficiencyand cost over the prior art.

Preferred embodiments of the present invention may include one or morekey identity and/or function indicators. Typically, such identity andfunction indicators permit a user to visually discern the identity ofthe positionable key 30. As is well known in the art, typical keyboardkey caps are often marked with labels that identify their function. Keycaps are usually labeled on their top or side surfaces to display theirfunction to a user.

One problem with positionable keys, however, is that their identity mustbe displayed along with their function. One method of identifying apositionable key 30 among a group of positionable keys 30 is to labeleach key with a unique ordinal number. Our research has found, however,that identifying a positionable key 30 by placing a number on the keycap 32 often confuses new users about its meaning. For example,displaying the number “5” on a key cap 32 often represents to anuntrained user that the function of a positionable key 30 is to producean input of a “5” character. This confusion between the key function andkey identity seems to occur even if we place the number on the side ofthe key cap 32.

Embodiments of the present invention can include a solution to the aboveproblem. Along these lines, at least one status and/or identityindicator may be included on one or both of the key cap and key base.For example, the embodiment shown in FIG. 16 includes a visible surface86 on the key base 34. The identity of the key may be displayed with anidentity label 84 on the visible surface 86. The identity label 84 mayuniquely identify a positionable key 30 among a group of positionablekeys 30 may include one or more letters, numbers, and/or symbols.Placing an identity label 84 on the key base 34 may improve theunderstanding of the distinction between key identity and key functionto untrained users. It may also free the surfaces of the key cap 32 toreceive intuitive markings or labels that reveal the key function.Supplying the visible surface 86 and the identity label 84 has resultedin increased comprehension of embodiments of the present invention.

Preferred embodiments of the present invention may also provide a meansto dynamically display the function of a positionable key 30. Unlike thekey identity, which is typically fixed at the time of manufacture, thefunction of a positionable key 30 may vary greatly depending on theneeds of the user. A user may change the function of a positionable key30 depending on the current software that the user is working with, forexample. A display key cap 88 may be substituted for the key cap 32 inthe present invention. The display key cap 88 may include a dynamicdisplay means, or display 90 on one or more of its surfaces.

A function and/or identity display according to the present inventionmay also include an electronic display. Along these lines, the display90 may be of any known electronically modifiable type, including aliquid crystal display (LCD), an organic light emitting diode (OLED)display, or one of the various electronic ink type displays known in theart. The display 90 is dynamically changed to reflect the currentfunction of the positionable key 30. According to preferred embodiments,information may be sent to the display through radio frequency inductivecommunication with the reader 80. However, any other known wirelesscommunication means may be employed. The resonant circuit for thedisplay may be separate from the PCB 50. The display resonant circuitmay be mounted underneath the display key cap 88. The display 90 and theassociated electronics may be powered by inductive coupling with thereader 80, or by a battery or any other known means. The ability todisplay the function of a positionable key 30 by wireless communicationwith the reader 80 represents an important improvement to the prior art.

Preferred embodiments of the present invention may also includealternate arrangements of the coil 50 and the switch 70. For example,FIG. 18 shows a simplified cross sectional view of an embodiment of akey cap 32 and a key base 34. The key dome in FIG. 18 has been omittedfor clarity. The embodiment of a positionable key 30 shown in FIG. 18includes at least two improvements to the prior art. The firstimprovement includes a wound coil 92 (shown in cross section) embeddedwithin the housing of the key base 34. By incorporating the coil 92within the housing of the positionable key, the PCB 50 may be reduced insize, or even eliminated, as the IC 68 may be directly connected to thecoil element without the need for the underlying structure of the PCB50. Furthermore, the embedded coil 92 may also provide an improvedaverage internal area over the coil design shown in FIG. 10, resultingin a better flux capture capability for a given key footprint. Ofcourse, the coil 92 may also be applied to the inside wall, or theoutside wall of the key base 34 or the key cap 32 to produce a similarbenefit.

A second improvement included in the embodiment shown in FIG. 18includes providing an alternative switching means for the radiofrequency resonant circuit in the positionable key 30. Instead of usinga mechanical contact-type switch, a resonant switch 94 may be used. Insuch an embodiment, the resonant switch 94 may be attached to the keycap 32. The resonant switch 92 may be constructed of a ferrite material.However, resonant switches may be created with any material that affectsthe inductance or capacitance of a nearby circuit. As discussed in theU.S. patent application Ser. No. 10/246,762, to Rix et al. for “ComputerInput Device with Individually Positionable and Programmable InputMembers”, radio frequency inductive resonant circuits are stronglysensitive to changes in inductance and capacitance. Pressing the key cap32 brings the resonant switch 94 closer to the coil 92, increasing theoverall circuit inductance. Releasing the key cap 32 moves the resonantswitch 94 further away, decreasing the overall circuit inductance. Inpreferred embodiments, the radio frequency inductive circuit of thepositionable key 30 is design to be “in tune” when the key cap 32 ispressed, and “out of tune” when released. The resonant circuit of thepositionable key 30 is designed such that when the key cap 32 ispressed, the circuit is in tune, and the RFID chip may communicate. Whenthe key cap is released, the resonant circuit is out of tune, andtherefore does not communicate. This is just one potential means amongmany possible means to adjust the resonant characteristics of theinductive circuit to provide a switching mechanism upon actuation of thepositionable key 30. Another means could include adjusting the distanceto conductive surfaces, such as a metal plate, to change the circuitcapacitance. Alternately, the coil geometry could be modified uponactuation of the key to change its resonant characteristics. Any meansknow in the art that changes the resonant characteristics of aninductive circuit may be formulated to provide a switching means.

It is important to note that the two improvements shown in FIG. 18 aremerely illustrative of two independent improvements. The embedded coil92 and the resonant switch 94 may be used together, or they may beapplied individually, where appropriate.

1. An independently positionable key switch, comprising: a key baseincluding a key cap receiving opening and at least one gripping featureoperative to facilitate gripping of the key base; and an actuatable keycap arranged in the key receiving opening of the key base, the key capbeing actuatable between an unactuated position and an actuatedposition.
 2. The key switch according to claim 1, wherein the at leastone gripping feature comprises at least one of a side scoop, surfacetexture and surface contour.
 3. The key switch according to claim 2,wherein the surface contour comprises at least one of grooves and ridgesand the surface texture comprises at least one of bumps and depressions.4. The key switch according to claim 1, wherein the at least onegripping feature comprises at least one side scoop, wherein the sidescoop does not extend to the key cap receiving opening.
 5. The keyswitch according to claim 1, wherein the at least one gripping featurecomprises two side scoops arranged on opposite sides of the key base. 6.The key switch according to claim 5, wherein the side scoops do notextend to the key cap receiving opening.
 7. The key switch according toclaim 5, further comprising: a key base extension arranged between theside scoops and the key cap receiving opening.
 8. The key switchaccording to claim 5, wherein the side scoops have a size sufficient topermit gripping of the key base and removal of the key base from asurface without gripping the key cap.
 9. The key switch according toclaim 5, wherein a distance between the side scoops and the key capreceiving opening is sufficient to prevent gripping of the key cap whenthe side scoops are gripped to remove the key switch from or place thekey switch on a surface.
 10. The key switch according to claim 1,wherein the at least one gripping feature comprises at least one sidescoop and at least gripping feature on a surface of the side scoop. 11.(canceled)
 12. The key switch according to claim 1, wherein two oppositeportions of the side walls of the key base have a lower height.
 13. Thekey switch according to claim 12, wherein the lowered portion of theside wall of the key base has a height sufficient to minimize engagementwith the key base as the key cap is actuated.
 14. The key switchaccording to claim 1, further comprising; a key dome arranged within thekey cap and the key base, the key dome comprising a flexible operativeto bias the key cap in an unactuated position.
 15. The key switchaccording to claim 1, further comprising: guiding elements operative toguide the key cap as it is actuated.
 16. The key switch according toclaim 15, wherein the guiding elements comprise a post on one of the keybase and the key cap and a post receiving collar on another of the keybase and the key cap.
 17. The key switch according to claim 15, whereinthe guiding elements comprise at least one tab on at least one of thekey base and the key cap and at least one tab receiving recess includinga tab stop on another of the key base and the key cap.
 18. The keyswitch according to claim 1, further comprising: an adhesive on a bottomsurface of the key base, the adhesive operative to secure the key baseon a surface.
 19. The key switch according to claim 1, furthercomprising: at least one label on at least one of the key base and thekey cap, the at least one label indicating at least one of key identityand key function.
 20. (canceled)
 21. The key switch according to claim19, wherein the at least one label comprises an electronic display. 22.The key switch according to claim 1, wherein the key cap and the keybase are connectable without additional attached parts.
 23. The keyswitch according to claim 1, further comprising: an RF circuit coil. 24.The key switch according to claim 23, wherein the RF circuit coil isarranged in the key base.
 25. (canceled)
 26. The key switch according toclaim 1, further comprising: a printed circuit board comprising an RFcircuit coil, a switch and an integrated circuit; and a switch closingelement operative to close the switch.
 27. The key switch according toclaim 26, wherein the switch closing element is arranged on the key cap.28. The key switch according to claim 26, further comprising; a key domearranged within the key cap and the key base, the key dome comprising aflexible operative to bias the key cap in an unactuated position,wherein the switch closing element is arranged on the key dome. 29.(canceled)
 30. (canceled)
 31. An independently positionable key switch,comprising: a key base; an actuatable key cap operatively connected tothe key base, the key cap being actuatable between an unactuatedposition and an actuated position; and at least one of an identityindicator and a status indicator associated at least one of the key capand the key base.
 32. An independently positionable key switch,comprising: a key base; an actuatable key cap operatively connected tothe key base, the key cap being actuatable between an unactuatedposition and an actuated position; and a coil of a resonant radiofrequency inductive circuit incorporated in or on one of the key baseand the key cap.
 33. A method for switching a radio frequency inductivecircuit, the method comprising: bringing the circuit into and out ofresonance.